Abstract
Although Japanese cedar is a major cause of seasonal pollinosis, many other tree pollens such as Japanese cypress, pine, white birch, Japanese alder, and white oak cause sensitivity. The RAST of various tree pollens was investigated in 43 patients presenting with nasal allergy in our clinic in Kumamoto City between February and June, 1987. Twenty-five patients were found to be sensitive to Japanese cedar pollen and seven of the 25 were sensitive to muliple tree pollens. None of the patients were sensitive to any single tree pollen other than Japanese cedar. Sensitization to Japanese cypress can be partly explained by its antigeneity to Japanese cedar, but sensitization to multiple antigens which have no cross reactivity is difficult to explain. Patients with antigens to multiple tree pollens had an HLA type typical of patients with Japanese cedar pollinosis. This suggests that persons genetically susceptible to producing IgE antibody specific to Japanese cedar are likely to produce IgE antibodies to multiple tree pollens.
